Which of the following is most likely to be found on an electrical plan?

An electrical plan primarily focuses on the layout and specifications related to the electrical system of a building. This includes the positioning of power outlets, lighting fixtures, circuits, and other electrical components essential for the functionality of the electrical system.

Power outlets are a key component of an electrical plan as they indicate where users can plug in devices and appliances, which is vital for the organization and flow of the electrical system within the building. The inclusion of power outlets on an electrical plan helps ensure that the location and quantity meet the needs of the space being utilized.

On the other hand, water supply lines, roofing materials, and wall insulation specifications pertain to plumbing, structural, and thermal aspects of building design rather than electrical systems. Therefore, these elements would not typically be detailed in an electrical plan focused on electrical components, making power outlets the most relevant and logical choice for this context.